1. Field of the Invention
The present invention relates to an optical module and method of manufacturing the same, and to an optical transmission device.
2. Description of the Related Art
In recent years, there has been a trend toward increased speeds and volumes in data communications, and developments in optical communications continue. Generally, in optical communications, an electrical signal is converted to an optical signal, and the optical signal is transmitted through an optical fiber, then the received optical signal is converted to an electrical signal. The conversion between electrical signals and optical signals is done by optical elements.
For example, Japanese Patent Application Laid-Open No. 10-339824 discloses an optical fiber positioned and fixed on a platform in which a V-groove is formed, to constitute an optical module.
However, even when the optical fiber is positioned using the V-groove, there remains the problem that it is not possible to carry out positioning in the axial direction of the optical fiber. As a result, there is a possibility to damage the optical element by the contact with the end surface of the optical fiber.
The present invention solves this problem, and has as it object the provision of an optical module allowing damage to an optical element to be prevented, a method of manufacturing the same, and an optical transmission device.
(1) An optical module of one aspect of the present invention comprises:
an optical element having an optical section;
a platform on which the optical element and an optical waveguide are mounted; and
a stop for disposing one end surface of the optical waveguide in a state of non-contact with the optical section.
Since the optical element is mounted on the platform, the positioning of the optical waveguide and the optical section of the optical element can be carried out by positioning the optical waveguide with respect to the platform. Since the end surface of the optical waveguide is held in a state of non-contact with the optical section by the stop, damage to the optical section is prevented.
(2) In this optical module,
a conductive layer may be formed on the platform, and
the optical element may have at least one bump on a surface on which the optical section is formed.
(3) In this optical module,
a through hole may be formed in the platform, and
the optical section may be mounted on the optical element in a manner to oppose one opening of the through hole.
(4) In this optical module,
the optical waveguide may be inserted in the through hole,
the optical element may have at least one non-electrical-connection bump on the surface on which the optical section is provided, and
the non-electrical-connection bump may contact the one end surface of the optical waveguide, and may have a function to maintain a non-contact disposition of the optical waveguide with the optical section.
(5) In this optical module,
the optical waveguide may be inserted in the through hole, and
a first part of the bump may be formed in a position to be bonded to the conductive layer, and a second part of the bump may be formed in a position to contact the one end surface of the optical waveguide.
(6) In this optical module,
a projection may be formed in the through hole to reduce the diameter of the through hole,
the optical waveguide may be inserted in the through hole and
the projection may function as the stop that contacts the one end surface of the optical waveguide.
(7) In this optical module,
the through hole may have a recess accommodating the optical element at a first opening thereof opposite to a second opening thereof at which the optical waveguide is inserted.
(8) In this optical module,
a substrate may be mounted on the platform, the substrate having a through hole of which diameter is larger than the diameter of the through hole formed in the platform,
the through holes formed in the platform and the substrate may be connected,
the optical waveguide may be inserted in the through hole formed in the substrate, and
a part of one surface of the platform may function as a stop that contacts the one end surface of the optical waveguide.
(9) In this optical module,
the stop may contact the end surface of a cladding, avoiding a core of the optical waveguide.
(10) In this optical module,
the stop may be formed by an optically transmitting member, and
the stop may be formed at the one opening of the through hole so as to contact the one end surface of the optical waveguide.
(11) This optical module may further comprise a sealing portion for sealing at least an electrical connection portion of the optical element.
(12) In this optical module,
the sealing portion may comprise a first resin portion for sealing the electrical connection portion of the optical element, and a second resin portion for sealing the first resin portion.
(13) In this optical module,
the first resin portion may be softer than the second resin portion.
By this means, no large stress is applied to the electrical connection portion of the optical element, and therefore the connection is protected.
(14) An optical transmission device of another aspect of the present invention comprises:
a plurality of platforms;
a light-emitting element having a light-emitting section, and mounted on a first platform of the plurality of platforms;
a light-receiving element having a light-receiving section, and mounted on a second platform of the plurality of platforms, the second platform being different from the first platform;
an optical waveguide of which end portions being inserted into the first and the second platforms; and
a stop for disposing end surfaces of the optical waveguide in a state of non-contact with the light-emitting section and light-receiving section.
Since the light-emitting element and light-receiving element are mounted on respective platforms, the positioning of the optical waveguide and the light-emitting section or light-receiving section can be carried out by positioning the optical waveguide with respect to each platform. Since the end surface of the optical waveguide is held in a state of non-contact with the light-emitting section and light-receiving section by the stop, damage thereto can be prevented.
(15) This optical transmission device may further comprise:
a plug connected to the light-emitting element; and
another plug connected to the light-receiving element.
By this means, a plurality of electronic instruments can be connected by connecting the plugs to electronic instruments.
(16) A method of manufacturing an optical module as further aspect of the present invention comprises:
a step of mounting an optical element having an optical section on a platform; and
a step of positioning and attaching an optical waveguide with respect to the optical section, and
in the step of attaching the optical waveguide, an end surface of the optical waveguide may be held in a state of non-contact with the optical section by means of a stop.
Since the optical element is mounted on the platform, the positioning of the optical waveguide and the optical section of the optical element can be carried out by positioning the optical waveguide with respect to the platform. Since the end surface of the optical waveguide is held in a state of non-contact with the optical section by the stop, damage to the optical section is prevented.
(17) The method of manufacturing an optical module in this aspect may further comprise:
a step of forming a first resin portion by sealing the electrical connection portion of the optical element by means of a first resin; and
a step of forming a second resin portion by sealing the first resin portion by means of a second resin after the step of forming the first resin portion.
(18) In this method of manufacturing an optical module,
the first resin portion may be softer than the second resin portion.
Since no large stress is applied to the electrical connection portion of the optical element, the connection portion is protected.